Monitoring moisture in oil
Moisture in transformers Q&A eBook
The definitive eBook on the subject, this companion to our renowned webinar series is full of the latest practical and scientific advice on measuring moisture in power transformers. Filled with your actual questions answered by Vaisala's experts, this nearly 40-page eBook is a versatile manual for anyone whose business it is to maintain guard against and understand the effects of moisture in power transformers.

Your key benefits for transformers
Real-time measurement of relative saturation (%RS) e.g. for dielectric strength monitoring
- Real Time PPM output for absolute moisture measurement in transformer oils
- Excellent long-term stability
- Highly selective to water molecules
- Insensitive to additives or contaminants in oil
Picture: Effect of relative moisture saturation (%RS) on dielectric strength of transformer insulation oils.

Your key benefits for lubrication
- Real time relative saturation measurement helps plan maintenance advance and minimize unplanned maintenance
- Real-time measurement helps minimize damage to critical machinery and also to optimize dryer usage
- Excellent long term stability ensures a trouble free operation and reliability of readings.
- Insensitive to additives and contaminants ensures suitability for numerous lubrication oil applications.

Get all the gains
Robust reliability
Long-term stability
Rapid Response
Protect your machinery and minimize downtime
From power transformers to lubrication, and from maritime to pulp and paper Vaisala leads the leap into knowledge. With sensors built in our own cleanrooms, our robust technology offers long-term stable and precise measurements.
Download our eBook and get a full overview of moisture in oil.

Uniquely robust sensors
Vaisala’s HUMICAP® were the first ever capacitive sensors used to measure moisture in oil online, and have since become a virtual industry standard.
The sensors have specifically been developed to measure even very low moisture levels in oils — mineral, vegetable and synthetic. The HUMICAP® sensors, manufactured in Vaisala’s own cleanrooms, have seen use in all corners of the Earth and even Mars.

What is water activity (aw)?
Water activity is the amount of water in a substance relative to the total amount of water it can hold. It is defined in our application note, which you can download from the link below.

Insights, webinars and more
Moisture in oil products

Moisture in oil probe MMP8

Moisture and Temperature in Oil Transmitter Series MMT330

Moisture and Temperature Transmitter for Oil MMT162

Handheld Moisture and Temperature Meter for spot-checking in oil MM70

Moisture and Temperature Meter Series MMT310

Intrinsically Safe Humidity and Temperature Transmitter Series HMT370EX
Power Industry Solutions
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Contact us
Interested to receive more information on a specific application or product? Drop us a line, and we'll get back to you!